Tetra decoding

[RonnieUSA]

Yes i have sound a lot better than dsd.

DSD any version doesn't offer decoding of Tetra, so You shouldn't bring into the topic.

 

[sq5bpf]

DSD any version doesn't offer decoding of Tetra, so You shouldn't bring into the topic.

maybe he is comparing how the codecs sound like. imo ACELP sounds better than real AMBE, especially with background noise. you can also compare it with two radios.

and the codecs in DSD, implemented by mbelib, have slightly worse quality (although that might have changed, i haven't used dsd for a long time). so in fact he's right - it does sound better than DSD

 

[hansheesbeen]

Yep that's right... Use some different systems to decode different digital modes... ACELP sounds 100 times better than AMBE...

 

[FR3500]

Decoding tetra .wav recording ?

Hello to all;
I was just wondering, as don't have the required hardware and skills to decode Tetra and use telive software, which seems to be a great tool, but i can get a few ggod repeaters in Tetra here, maybe is there a way to record some, then send it to someone who could tell if there is some way to decode;
Just in order to know if the signal is good enough, and if these repeaters transmit in the clear?

I have a Uniden 3500, and i can record the discriminator in 48 khz
If someone interested in that option, would you contact me please?

Best regards , thanks for your support

 

[yo4tnv]

AMD APU A6/quad core@2.7Ghz/4G ram >Fresh install of Lubuntu 14.10 > buildgnuradio -o > Make failed
Now running buildgnuradio -o -v -ja (multiple jobs and verbose) to catch the error somehow..

AT THE VERY START OF buildgnuradio
"couldn`t find package python-gnuradio*"


ENDS BADLY

[ 87%] Building CXX object gr-blocks/lib/CMakeFiles/gnuradio-blocks.dir/tag_gate_impl.cc.o
Linking CXX shared library libgnuradio-blocks-3.6.5.1.so
[ 87%] Built target gnuradio-blocks
Makefile:143: recipe for target 'all' failed
make: *** [all] Error 2
make failed
Exiting Gnu Radio build/install

Switching to Debian 7.7 netinstall/64

 

[yo4tnv]

[ 87%] Building CXX object gr-blocks/lib/CMakeFiles/gnuradio-blocks.dir/tag_gate_impl.cc.o
Linking CXX shared library libgnuradio-blocks-3.6.5.1.so
[ 87%] Built target gnuradio-blocks
Makefile:143: recipe for target 'all' failed
make: *** [all] Error 2
make failed
Exiting Gnu Radio build/install

Switching to Debian 7.7 netinstall/64

 

[yo4tnv]

"Something is rotten in Denmark"....
I tried again to compile gnuradio on xubuntu 13.10/64, installed pre-requisites, but failed at 94%
might the -ja/ -j4 be a mistake ?
As far as I read Debian 7 might be optimal but asked me of specific kernel to install, etc.
Did any of you succeeded to build it flawlessly and on what distribution ?

 

[sq5bpf]

"Something is rotten in Denmark"....
I tried again to compile gnuradio on xubuntu 13.10/64, installed pre-requisites, but failed at 94%
might the -ja/ -j4 be a mistake ?

might be a problem with -j, sometimes parallel builds can fail if not done correctly

the build-gnuradio from SBRAC if very plug-and-play and was tested by a lot of people, so no idea why it might fail.

maybe you are missing some package which i always install? (please post the error messages from the compil elog)

As far as I read Debian 7 might be optimal but asked me of specific kernel to install, etc.
Did any of you succeeded to build it flawlessly and on what distribution ?

i usually use build-sbrac to build gnuradio, because it takes care of everything, used it on different flavours of debina 6 and debian 7 and it worked every time.

i will probably be doing a fresh install of debian 7.7 on a new laptop within the next few days, and will also check if this build scripts works correctly (but there is no reason for it to not work)

 

[yo4tnv]

Right now I whacked the xubuntu setup that failed and installing Debian 7.7 (DVD1 iso image on USB stick). First time pure Debian. Finger crossed
Would be nice to know gnuradio 3,7 branch will be tweaked to be buildgnuradio friendly. Looking forward to it.
I`ll keep you updated.

 

[yo4tnv]

":Unsuported version Debian 7.7" Then, which one?
Anyway.. I had enough for today...
edited buildgnuradio to make it aware of 7.7
compiling rolls again

 

[sq5bpf]

edited buildgnuradio to make it aware of 7.7
compiling rolls again

for the benefit of other readers and google it should be mentioned that details of what to modify are in the telive documentation

 

[yo4tnv]

for the benefit of other readers and google it should be mentioned that details of what to modify are in the telive documentation

I saw that mention in the telive docs but... too late..
Now, compiling worked, all stuff lauched without errors but grc 1ch demo does nothing, throwing an 3DNow error ...
I`ll dig deeper..

... a matter of r820t not properly recognised in USB 3.0 slot

Now I do have the image of waveform on 1chdemo graph but static. Something`s still rotten....

... rebooting the system fixed this, now i have a real nice dancing signal and the finetune works too! Hooray!

 

[sq5bpf]

Now I do have the image of waveform on 1chdemo graph but static. Something`s still rotten..

a common problem is inputing the frequency the way gnuradio wants it. for example to use 420.2125MHz you could enter 420M (and press enter) for the baseband frequency, 212.5k (and press enter) for the offset. there is a label that shows frequency, this should show 420.212MHz (only shows 3 kHz digits, don't worry about it). try to avoid 0kHz offset. also make sure you have the right ppm value (you can tweak it later by adjusting the ppm slider)

before running gnuradio try to run rtl_fm and see if you can receive a local broadcast station

some people reported that everything started working after a reboot.

 

[yo4tnv]

That`s what I end up with after inserting a known frequency (SDR#) minus 500khz and launcing ./receiver1 1

BURST
CRC COMP: 0x1d0f OK
SB1 32/16/2/000 type1: 000100000110100001000000000000000111000100001000101011110001
TMB-SAP SYNC CC 000001(0x01) TN 10(2) FN 10000(16) MN 100000(32) MCC 0011100010(226) MNC 00010001010111(1111)
TMV-UNITDATA.ind 32/16/2/000 BSCH CRC=1 SYNC
TMV-UNITDATA.ind 32/16/2/000 AACH CRC=1 ACCESS-ASSIGN
ACCESS-ASSIGN PDU: DL_USAGE: Unallocated UL_USAGE: Unallocated
CRC COMP: 0x1d0f OK
SB2 32/16/2/000 type1: 1000111001100000001111000000101001101110011100000000000100001101111000100000000000001000000100111111111111111111110101100111
TMV-UNITDATA.ind 32/16/2/000 UNKNOWN CRC=1 BROADCAST
BNCH SYSINFO (DL 392012500 Hz, UL 382012500 Hz), service_details 0x0d67 CCK ID 16
Advanced link: 1
Air encryption: 1
SNDCP data: 1
unknown 0x8: 0
Circuit data: 0
Voice service: 1
Normal mode: 1
Migration supported: 0
Cell never uses minimum mode: 1
Priority cell: 0
De-registration mandatory: 1
Registration mandatory: 1

so, it`s definetely TETRA !! )

 

[sq5bpf]

so, it`s definetely TETRA !! )

yes it is

i see that the network can use encryption, but there might be some unencrypted signals too (the per-radio encryption license costs can be high, so maybe this was spared for not so important communications). to find out enable recording, mutessi, and logging (and mute if you don't want to bother yourself with occasional audio) and leave it on for a few days. you should have some OGG files in /tetra/out (provided that tetrad is working and that the tetra codecs are installed correctly).

now get some music player that supports OGG (for example audacious), and listen to all of them in your spare time. many will be just snippets of unreadable encrypted audio, but some might be more interesting.

 

[yo4tnv]

I have 4 more signals to look for, but.. tomorrow or in weekend..
I have 12 hours now since I stand this "fight" to make it work..
Live to fight another day... )

Have a nice one, man !

 

[sq5bpf]

I have 4 more signals to look for

this is why it is possible to implement a multi-channel receiver with this software, look in the documentation.

the software is very modular:

you can use a single dongle to monitor multiple channels in 2.4MHz of spectrum, and you can have multiple dongles (each with its own gnuradio receiver), each monitoring it's own 2.4MHz slice of the spectrum.

the number of channels monitored depends on the cpu and memory. i can do 4 channels with an old laptop, a modern workstation will probably do a few times that.

then you can feed the channels to multiple telive instances. the most common use would be to use one telive instance per network.

 

[signal4567]

Software works good, however i am getting this stuttering in the audio mostly at the beginning of a voice call and sometimes randomly during the call.
Getting the same results with both VM and a physical machine.
Signal strength is very strong.

 

[sq5bpf]

Software works good, however i am getting this stuttering in the audio mostly at the beginning of a voice call and sometimes randomly during the call.

is this only during live monitoring, or also on the recordings? (if also on the recordings then please send me a few samples)

there might be a very small stutter at the last second of live monitoring (but not on the recording), this is a known bug, that i don't intend to fix right now.

 

[sammy3418]

Software works good, however i am getting this stuttering in the audio mostly at the beginning of a voice call and sometimes randomly during the call.
Getting the same results with both VM and a physical machine.
Signal strength is very strong.

Hi buddy,

Did you run into any problems with VMware? having driver problems on mint and Ubuntu... Dont suppose you have an idiots guide for black listing drives? I am not a total dunce with Linux i would give myself a basic rating on it... I've installed all the software but when I start gnuradio up its giving me a fatal error..seem to have everything covered just this part is giving me problems.. I really would like to get this software going... Tried this code from someone on the forum sudo rmmod dvb_usb_rtl28xxu it does start the dongle up via the rtl_test this is what I get with that command

Using device 0: Generic RTL2832U OEM
Found Rafael Micro R820T tuner
Supported gain values (29): 0.0 0.9 1.4 2.7 3.7 7.7 8.7 12.5 14.4 15.7 16.6 19.7 20.7 22.9 25.4 28.0 29.7 32.8 33.8 36.4 37.2 38.6 40.2 42.1 43.4 43.9 44.5 48.0 49.6
Sampling at 2048000 S/s.

Info: This tool will continuously read from the device, and report if
samples get lost. If you observe no further output, everything is fine.

Reading samples in async mode...
lost at least 36 bytes

Any ideas ?

Thanks dude

Sam